Jack McInerney (10 goals) and Conor Casey (nine) have combined for more than half of the Philadelphia Union’s total (36).

The first time these teams met this season, March 16, McInerney scored a late goal in Philadelphia and the Union took 3 points.

But on April 27, the Revolution shut down the high-scoring duo at Gillette Stadium and won, 2-0. Casey didn’t even register a shot, and was subbed out after an hour.

Revolution coach Jay Heaps is well aware of the tall task that comes with defending against the Union (10-7-8, 38 points), who have failed to score in only four MLS games this season.

“McInerney is a very elusive player,” said Heaps. “He’s got a good sense of when to go forward, and he’s always dangerous.”

But McInerney is just one piece of the puzzle Revolution defenders will have to solve.

“For me, Casey makes [McInerney] that much better,” said Heaps. “Casey is a lot more active in the buildup, which allows McInerney to get behind. Casey plays more underneath and holds it, and creates little gaps, and so Casey’s very dangerous in the attack. Both those guys are better with service, and if we can limit the service, then we’ll have a better chance.”

Revolution defender A.J. Soares made his second start since April last weekend. He played a pivotal role in keeping Magee quiet, and believes McInerney’s playing style is similar.

“[McInerney] is a very good forward, and we’ve got to be mindful of where he’s running,” said Soares. “He likes to do a lot of those things that Magee does, where he finds those spaces that you don’t expect him to run . . . he gets in behind you, always peeling off the back line.”

After the win over Chicago, Heaps didn’t credit an individual or the defenders. The coach said it was a team effort, starting with the forwards and midfielders.

Soares acknowledged that if the Revolution (9-9-6, 33 points) are to stop McInerney and Casey’s touches, the defensive pressure needs to start with the Revolution players up front.

“We need to get pressure up the field so they don’t have free service, so it’s predictable where they’re going to go with the ball,” Soares said.

A major talking point before the game against Chicago was New England’s slow starts.

In the previous three games, against D.C. United, Toronto FC, and Sporting KC, the Revolution gave up the first goal, leading to 6 dropped points.

But they looked revitalized and focused from the first whistle against the Fire. And Heaps hopes his team can replicate that for 90 minutes on Sunday night.

“You can say a lot about giving up goals, and giving up the first goal, that’s always a part of it,” Heaps said. “But it’s also the attitude and energy in which you start the game, and I think when we do that well, we play well.”